s_fpclassifyl.c 1.5 KB

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  1. /* Return classification value corresponding to argument.
  2. Copyright (C) 1997-2026 Free Software Foundation, Inc.
  3. This file is part of the GNU C Library.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <https://www.gnu.org/licenses/>. */
  15. #include <math.h>
  16. #include <math_private.h>
  17. int
  18. __fpclassifyl (long double x)
  19. {
  20. uint32_t ex, hx, lx;
  21. int retval = FP_NORMAL;
  22. GET_LDOUBLE_WORDS (ex, hx, lx, x);
  23. ex &= 0x7fff;
  24. if ((ex | lx | hx) == 0)
  25. retval = FP_ZERO;
  26. else if (ex == 0 && (hx & 0x80000000) == 0)
  27. retval = FP_SUBNORMAL;
  28. /* Pseudo-normals, i.e. pseudo-zero, pseudo-infinity and un-normals. They
  29. behave like NaNs, so categorize them as such. */
  30. else if ((hx & 0x80000000) == 0)
  31. retval = FP_NAN;
  32. else if (ex == 0x7fff)
  33. retval = ((hx & 0x7fffffff) | lx) != 0 ? FP_NAN : FP_INFINITE;
  34. return retval;
  35. }
  36. libm_hidden_def (__fpclassifyl)